Hot water pump with removable shaft bearing

ABSTRACT

This invention relates to an improvement in a hot water pump having a removable shaft bearing in the upper pump part and including a shaft, a pump cover, a sealing housing, an outer and an inner supporting tube, and a lower shaft bearing. The improvement comprises lower shaft bearing means having an outside diameter smaller than the inside diameter of the sealing housing and the inner supporting tube, whereby the lower shaft bearing may be pulled out through said inner supporting tube and sealing housing.

United States Patent 1191 1111 3,822,962 Wieser 1 July 9, 1974 [54] HOT WATER PUMP WITH REMOVABLE 3,189,264 6/1965 Becker 415 175 3,205,825 9/1965 Rupp 415/201 SHAFT BEARING 3,457,869 7/1969 Janetz 1 415/98 [75] Inventor: Rudolf W1eser, Vo1tsberg, Germany 3,532,443 10/1970 Johnson 308/76 [73] Assignee: Maschinenfabrik Andritz FOREIGN PATENTS OR APPLICATIONS Acfiengesellschafl 167,529 8/1921 Great Britain 415/111 22 Filed: Ma 23, 1972 l 1 y Primary ExaminerChar1es J. Myhre 1 1 p 255,977 Assistant Examiner-R. H. Lazarus Attorney, Agent, or Firm-James E. Bryan, Esquire [301 Foreign Application Priority Data June 29, 1971 Austria 5635/71 ABSTRACT ThlS 1nvent1on relates to an improvement 1n a hot [52 us. c1. 415/201, 308/77 Water P having a removable Shaft bearing in the 51 Int. Cl. F0ld 1/02 PP P P and including a shaft 8 P Cover, 58 1 Field of Search 415/175, 178,201, 199 R, a Sealmg housing, an Outer q an Inner Supporting 415/199 A, 131; 308/362, 361 76 77 tube, and a lower shaft bearmg. The lmprovement comprises lower shaft bearing means having an out- [56] References Cited side diameter smaller than the inside diameter of the sealing housing and the inner supporting tube, UNITED STATES PATENTS whereby the lower shaft bearing may be pulled out 2,314,703 3/1943 Howarth 308/76 through Said inner Supporting tube d Sealing hous 2,929,646 3/1960 Smlth 415/175 g 3,104,921 9/1963 Newcomer 308/76 3,183,047 5/1965 Ribble 415/201 9 Claims, 6 Drawing Figures HOT WATER PUMP WITH REMOVABLE SHAFT BEARING The present invention relates to a hot water pump with a removable shaft bearing in the upper pump portion. The pump includes a pump cover, a sealing housing, an outer and an inner supporting tube, and a lower shaft bearing, as well as, if desired, an internal cooler.

Hot water pumps are employed, inter alia, in atomic power stations as main coolant pumps, as well as circulating pumps of LaMont boilers. The temperature of the flow medium thereof may be up to 300C and the operating pressure thereof may be up to 160 atmospheres gauge. Such hot water pumps are generally built in a single stage and produce a pressure increase of approximately to 12 atmospheres.

In order to render it possible that the shaft packings which are positioned in the sealing housings can be taken out and checked without requiring that the upper shaft bearing and the pump motor be dismantled at the same time, a detachable shaft piece or portion is provided in the hot water pumps, in known manner.

In order to further make it possible that, during inspection of the lower shaft bearingatwhich time it is pulled out of the hot water pump, the upper shaft bearing and the pump motor need not be dismantled, in the hot water pump proposed by the present invention the shaft bearing is disposed either below or within an inner supporting tube, the outside diameter of the shaft bearing is smaller than the inside diameter of the sealing housing, and is also smaller than the inside diameter of the inner supporting tube and of the internal cooler. The shaft bearing is adapted to be pulled out through the inner supporting tube, the internal cooler, and the sealing housing.

Further features andadvantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein FIG. I is a longitudinal cross-sectional view through the upper pump part of an axial pump without an internal cooler;

FIG. 2 is a longitudinal cross-sectional view through a pump cover with a screwed-in sealing housing and an air guiding collar;

FIG. 3 is a longitudinal cross-sectional view through a pump cover which is supported at the pump housing upon an inner sealing surface and an outer supporting surface, and whose bracket is connected with the upper, cooler cover portion by means of a reinforcement, the sealing housing being inserted from below in the cover bracket;

FIG. 4 is a longitudinal cross'sectional view through the upper pump part or portion of an axial pump with an internal cooler, in which case the inner supporting tube is screwed to the lowermost flange of the outer supporting tube;

FIG. 5 is a local horizontal cross-sectional view through the internal cooler, taken along line V-V of FIG. 4, and

FIG. 6 illustrates as detail C in FIG. 4 the detachable screwed connection between the two halves of the protective shaft sleeve.

In the embodiment according to FIG. 1, the pump shaft 1 carries with the lower shaft collar 2 the wheel 3. The removable shaft piece or portion 4 is disposed between the pump and the upper pump bearing (not shown), and the pump motor. The pump cover 5 is screwed to the pump housing 7 by means of the cover screws 6. The pump cover has a downwardly extending cylindrical bracket 8 which is connected at the lower end thereof with the lower end of the sealing housing 9 by means of a tongue and groove connection and a buttress thread. Between the outer jacket of the sealing housing 9 and the inner jacket of the pump cover 5 and the bracket 8 thereof, there remains an annular air space 10 which is in communication with the surrounding outer area. Arranged within the sealing housing 9 are the shaft packings 11. The high-pressure lines 12, indicated in dash-dotted lines, to and from the sealing housing 9 (sealing water supply leakage discharge) are positioned slightly above the pump cover and are guided outwardly under the motor carrier 13.

The outer supporting tube 14 is secured to the pump cover 5 and carries at the lower end thereof the distributor 14a. Disposed below the bracket 8 of the pump cover 5 is the inner supporting tube 15 which is guided with the lower end thereof in the outer supporting tube 14. The hollow space 16 between the inner supporting tube 15 and the outer supporting tube 14 has an annular cross-section and is filled with burled sheets which are coiled upon the bracket 8 of the pump cover 5 and upon the inner supporting tube 15. The stagnant water which is present within the narrow gaps between the burled sheets has an excellent insulating effect.

Disposed inside the inner supporting tube 15 and in the lower area of the sealing housing 9 is the doublewalled cold water storage reservoir 17a, 17b which is partitioned or subdivided in the center thereof. Accommodated in the upper portion thereof, towards the packings ll of the sealing housing 9, is an insulation 18. Two storage chambers 19 are arranged below the inner jacket of the cold water storage reservoir 17a, 17b. The lower shaft bearing 20 with the bushing 20a thereof is movably secured at the bottom of the cold water storage reservoir and sealed off by means of the metallic bellows 21. The radial positioning of the lower shaft bearing 20 is brought about and obtained by means of four wedges 22 in the outer supporting tube 14. The lower shaft bearing 20 may be pulled out upwardly through the sealing housing 9 with the cold water storage reservoir 17a, 17b. All of the removable parts have been identified by stippled hatching.

The plastic sealing rings or gaskets 22a of the cold waterstorage reservoir 17a, 17b are positioned within the area of the sealing housing 9.

The protective shaft sleeve 23a, 23b is equally parti tioned or subdivided and carries at the bottom the bushing 24 on the side of the shaft. The detachable connection of the two halves 23a, 23b of the protective shaft sleeve is accomplished by means of the bolts 25 and nuts 26 (show in detail in FIG. 6).

Provided below the lower shaft bearing 20 is a mixing chamber 27 which is enclosed with an annular insulating body 28 that encloses also the shaft collar 2 and the lower half of the bearing 20.

Disposed at the outside of the sealing housing 9 are cooling water channels or ducts 29. The guide of the supply and discharge lines 30 for the cooling water (shown in dash-dotted lines) is effected from above through the annular air space 10.

The modified embodiment according to FIG. 2 comprises within the annular air space 10 between the pump cover 5 and the sealing housing 9 an air guiding collar 31 which is connected at the top with the sealing housing 9 and open at the bottom. An air supply line 32 tangentially adjoins the air guiding collar 31 in the upper area or zone thereof. Cooling ribs 33 are cast on at the outer jacket of the pump cover 5 for the purpose of reducing the cover temperature.

The modified embodiment according to FIG. 3 dis closes a pump cover 5 whose bracket 8 is connected with the upper cooler cover portion via a reinforcement 34. The sealing housing 9 is inserted from below into the cover bracket 8 and screwed thereto from below.

The annular space position between the pump cover 5 and the cover bracket 8 is filled with an insulation, for example the burled sheets 35. Provided at the inner jacket of the cover bracket 8 are the cooling ribs 36.

In this particular embodiment, the cover is supported not only upon the inner sealing surface 37, but also upon the outer supporting surface 38 of the pump housing, and in this case the cover screws 6 are disposed as closely as possible to the sealing surface 37. For purposes of an improved cooling of the cover, horizontal and vertical cooling bores 39 are arranged therein.

This type of provision for the cover and the sealing housing is particularly interesting for short hot water pumps in which the sealing housing cannot be arranged as deeply within the pump housing.

In the embodiment according to FIG. 4, in which the reference numerals have the same significance as in FIG. 1, the pump has an internal cooler with annular cross-section. The inner cooler jacket 40 and the outer cooler jacket 41 are supported against each other via the ribs 42. Between the ribs 42, there are channels 43 through which the cooling water flows. The inner jacket 40 and the outer jacket 41 of the cooler are welded to the sealing housing 9. The guide of the supply and discharge lines 30 for the cooling water is effected from above through the annular air space between the sealing housing 9 and the pump cover 5, and the cover bracket 8. The lower end of the cooler is axially guided within the inner supporting tube and radially held in position. The outerjacket 41 ofthe cooler has at the outside thereof the cooling ribs 44 (FIG. 5).

Disposed in the cooler in two normal axial planes are the radial bores 45 and 46. It is through these bores that the lubricating water (and the hot water, in case of failure of the sealing water) passes from the inside of the cooler to the outside thereof. and then back again to the inside.

Disposed inside the cooler is the divided supporting tube 47a, 47b. It is so shaped that it will form, over a part of the pump height, a long narrow throttling gap with the protective shaft sleeve 23a, 23b. On the other hand. the supporting tube 47a, 47b makes contact with the three flanges thereof with the inner surface of the cooler and of the sealing housing 9. Arranged at these contact surfaces are the plastic sealing rings 48a, 48b and 48c of the supporting tube 47a, 47b. A burled sheet insulation 18 is provided for below the upper flange of the lower supporting tube portion 47b.

Further disposed in the lower supporting tube portion 47b is a guiding cylinder 49 whose lower end is connected with the lower flange of the lower support ing tube portion 47b.

In this embodiment, the lower shaft bearing 20 is similarly secured at the bottom at the lower supporting tube portion 47b, but it is radially held in the inner supporting tube 15 by means of four wedges 22 which allow for a relative axial movement between the shaft bearing 20 and the inner supporting tube 15.

The protective shaft sleeve 23a, 23b is equally divided into two portions and the halves thereof are detachably interconnected by means of the bolts 25 and nuts 26.

The bushing 24 on the side of the shaft at the lower end of the protective shaft sleeve 23a, 23b may be pulled out through the supporting tube 47a, 47b since the outside diameter thereof is smaller than the inside diameter of the supporting tube.

For the pump as proposed in FIG. 4, the inner supporting tube 15 is so provided and arranged that. at the lower end thereof, it is rigidly screwed to the lower flange of the outer supporting tube 14 while it is radially held with the upper end thereof within the sealing housing 9 and is axially movably guided. By virtue of this characteristic, a relative movement between these two elements is possible, which will arise because of the varying expansions due to different degrees of heating.

By virtue of this construction of the inner supporting tube 15, there will be produced in the pump only a single, large, cohesive annular chamber or space 16 which is filled with burled sheeting or with another insulating material. This annular space has no heat bridges. As a result, the lower shaft bearing 20 remains considerably cooler than is the case if it is radially supported against the outer supporting tube 14.

It will be obvious to those skilled in the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

What is claimed is:

1. In a hot water pump having a removable shaft bearing in the upper pump part and including a shaft, a pump cover, a sealing housing, an outer and an inner supporting tube, and a lower shaft bearing,

the improvement which comprises lower shaft bearing means having an outside diameter smaller than the inside diameter of the sealing housing and the inner supporting tube, whereby the lower shaft bearing may be pulled out through said inner supporting tube and sealing housing.

2. A pump according to claim 1 including an internal cooler having an inside diameter greater than the outside diameter of said lower shaft bearing. I

3. A pump according to claim 2, in which the shaft bearing means is secured to the lower end of an extractable supporting tube which is positioned in the inner supporting tube and in the internal cooler, and in the lower portion of the sealing housing.

4. A pump according to claim 2, in which for the purpose of keeping the lower shaft bearing means cool, a space filled with an insulation is positioned between the outer supporting tube and the inner supporting tube and is elongated downwardly to under the lower shaft bearing means and so as to reach around a mixing chamber.

5. A pump according to claim 2, in which for the purpose of receiving the lower shaft bearing means, the

inner supporting tube is positioned between the sealing housing and the outer supporting tube.

6. A pump according to claim 1, in which the lower shaft bearing means is secured to the lower end of an extractable cold water storage reservoir which is positioned within the inner supporting tube and in the lower area of the sealing housing.

7. A pump according to claim 1, in which the shaft bearing means is radially held in the outer supporting tube by means of wedges and is axially guided.

8. A pump according to claim 1, in which a protective shaft sleeve is so dimensioned that the outside diameter thereof and the outside diameter of a bushing positioned at the lower end thereof on the side of the shaft are smaller than the inside diameter of a cold water storage reservoir and the inside diameter of the inner supporting tube, whereby the protective shaft sleeve with the bushing on the side of the shaft is adapted to be pulled out through the cold water storage reservoir, the inner supporting tube, and the sealing housing.

9. A pump according to claim 8, in which the protective shaft sleeve is divided and the parts thereof are detachably interconnected. 

1. In a hot water pump having a removable shaft bearing in the upper pump part and including a shaft, a pump cover, a sealing housing, an outer and an inner supporting tube, and a lower shaft bearing, the improvement which comprises lower shaft bearing means having an outside diameter smaller than the inside diameter of the sealing housing and the inner supporting tube, whereby the lower shaft bearing may be pulled out through said inner supporting tube and sealing housing.
 2. A pump according to claim 1 including an internal cooler having an inside diameter greater than the outside diameter of said lower shaft bearing.
 3. A pump according to claim 2, in which the shaft bearing means is secured to the lower end of an extractable supporting tube which is positioned in the inner supporting tube and in the internal cooler, and in the lower portion of the sealing housing.
 4. A pump according to claim 2, in which for the purpose of keeping the lower shaft bearing means cool, a space filled with an insulation is positioned between the outer supporting tube and the inner supporting tube and is elongated downwardly to under the lower shaft bearing means and so as to reach around a mixing chamber.
 5. A pump according to claim 2, in which for the purpose of receiving the lower shaft bearing means, the inner supporting tube is positioned between the sealing housing and the outer supporting tube.
 6. A pump according to claim 1, in which the lower shaft bearing means is secured to the lower end of an extractable cold water storage reservoir which is positioned within the inner supporting tube and in the lower area of the sealing housing.
 7. A pump according to claim 1, in which the shaft bearing means is radially held in the outer supporting tube by means of wedges and is axially guided.
 8. A pump according to claim 1, in which a protective shaft sleeve is so dimensioned that the outside diameter thereof and the outside diameter of a bushing positioned at the lower end thereof on the side of the shaft are smaller than the inside diameter of a cold water storage reservoir and the inside diameter of the inner supporting tube, whereby the protective shaft sleeve with the bushing on the side of the shaft is adapted to be pulled out through the cold water storage reservoir, the inner supporting tube, and the sealing housing.
 9. A pump according to claim 8, in which the protective shaft sleeve is divided and the parts thereof are detachably interconnected. 